scholarly journals The roles of exosomal immune checkpoint proteins in tumors

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Cheng Xing ◽  
Heng Li ◽  
Rui-Juan Li ◽  
Le Yin ◽  
Hui-Fang Zhang ◽  
...  
Keyword(s):  
Immune Checkpoint ◽  
Cytotoxic T Lymphocyte ◽  
Early Stage ◽  
Immune Checkpoints ◽  
Therapeutic Effects ◽  
Checkpoint Proteins ◽  
Adaptive Resistance ◽  
Arginase 1 ◽  
Programmed Death ◽  
Immune Checkpoint Proteins

AbstractTargeting immune checkpoints has achieved great therapeutic effects in the treatment of early-stage tumors. However, most patients develop adaptive resistance to this therapy. The latest evidence demonstrates that tumor-derived exosomes may play a key role in systemic immune suppression and tumor progression. In this article, we highlight the role of exosomal immune checkpoint proteins in tumor immunity, with an emphasis on programmed death ligand 1 (PD-L1) and cytotoxic T lymphocyte-associated antigen 4 (CTLA-4), as well as emerging evidence on roles of T cell immunoglobulin-3 (TIM-3), arginase 1 (ARG1), and estrogen receptor binding fragment-associated antigen 9 (EBAG9) expressed by exosomes.

scholarly journals Molecular Interactions of Antibody Drugs Targeting PD-1, PD-L1, and CTLA-4 in Immuno-Oncology

Molecules ◽  
2019 ◽  
Vol 24 (6) ◽  
pp. 1190 ◽  
Author(s):  
Hyun Lee ◽  
Sang Lee ◽  
Yong-Seok Heo
Keyword(s):  
Molecular Interactions ◽  
Immune Checkpoint ◽  
Rational Design ◽  
Cytotoxic T Lymphocyte ◽  
Immune Surveillance ◽  
Structural Studies ◽  
Checkpoint Proteins ◽  
Wide Range ◽  
Programmed Death 1 ◽  
Immune Checkpoint Proteins

Cancer cells can evade immune surveillance through the molecular interactions of immune checkpoint proteins, including programmed death 1 (PD-1), PD-L1, and cytotoxic T lymphocyte-associated antigen 4 (CTLA-4). Since 2011, the FDA-approved antibody drugs ipilimumab (Yervoy®), nivolumab (Opdivo®), pembrolizumab (Keytruda®), cemiplimab (Libtayo®), atezolizumab (Tecentriq®), durvalumab (Imfinzi®), and avelumab (Bavencio®), which block the immune checkpoint proteins, have brought about a significant breakthrough in the treatment of a wide range of cancers, as they can induce durable therapeutic responses. In recent years, crystal structures of the antibodies against PD-1, PD-L1, and CTLA-4 have been reported. In this review, we describe the latest structural studies of these monoclonal antibodies and their interactions with the immune checkpoint proteins. A comprehensive analysis of the interactions of these immune checkpoint blockers can provide a better understanding of their therapeutic mechanisms of action. The accumulation of these structural studies would provide a basis that is essential for the rational design of next-generation therapies in immuno-oncology.

scholarly journals Immune Checkpoints as Promising Targets for the Treatment of Idiopathic Pulmonary Fibrosis?

2019 ◽  
Vol 8 (10) ◽  
pp. 1547 ◽  
Author(s):  
JanWillem Duitman ◽  
Tom van den Ende ◽  
C. Arnold Spek
Keyword(s):  
Idiopathic Pulmonary Fibrosis ◽  
Pulmonary Fibrosis ◽  
Immune Checkpoint ◽  
Checkpoint Inhibitors ◽  
Immune Checkpoints ◽  
Checkpoint Inhibition ◽  
Immune Checkpoint Inhibition ◽  
General Role ◽  
Checkpoint Proteins ◽  
Immune Checkpoint Proteins

Idiopathic pulmonary fibrosis is a rare, progressive and fatal lung disease which affects approximately 5 million persons worldwide. Although pirfenidone and/or nintedanib treatment improves patients’ wellbeing, the prognosis of IPF remains poor with 5-year mortality rates still ranging from 70 to 80%. The promise of the anti-cancer agent nintedanib in IPF, in combination with the recent notion that IPF shares several pathogenic pathways with cancer, raised hope that immune checkpoint inhibitors, the novel revolutionary anticancer agents, could also be the eagerly awaited ground-breaking and unconventional novel treatment modality limiting IPF-related morbidity/mortality. In the current review, we analyse the available literature on immune checkpoint proteins in IPF to explore whether immune checkpoint inhibition may be as promising in IPF as it is in cancer. We conclude that despite several promising papers showing that inhibiting specific immune checkpoint proteins limits pulmonary fibrosis, overall the data seem to argue against a general role of immune checkpoint inhibition in IPF and suggest that only PD-1/PD-L1 inhibition may be beneficial.

scholarly journals Expression and Significance of Immune Checkpoints in Clear Cell Carcinoma of the Uterine Cervix

2020 ◽  
Vol 2020 ◽  
pp. 1-7 ◽  
Author(s):  
Liju Zong ◽  
Qianqian Zhang ◽  
Yuncan Zhou ◽  
Yujia Kong ◽  
Shuangni Yu ◽  
...  
Keyword(s):  
Cell Carcinoma ◽  
T Cell Activation ◽  
Immune Checkpoint ◽  
Cell Activation ◽  
Clear Cell ◽  
Clear Cell Carcinoma ◽  
Immune Checkpoint Blockade ◽  
Immune Checkpoints ◽  
Checkpoint Proteins ◽  
Immune Checkpoint Proteins

The purpose of this study was to investigate the expression levels of the immune checkpoint proteins, programmed cell death-ligand 1 (PD-L1), B7-H3, B7-H4, and V-domain Ig suppressor of T cell activation (VISTA), as well as the significance thereof, in clear cell carcinoma (CCC) of the cervix (a rare histological subtype of cervical cancer). We also compared the expression statuses of these biomarkers in cervical CCCs with those in cervical squamous cell carcinomas (SCCs). We evaluated the expression of PD-L1, B7-H3, B7-H4, and VISTA in 50 cervical CCCs and 100 SCCs using immunohistochemical staining and investigated the associations between these markers, clinicopathologic features, and survival in patients with CCCs. Of the cervical CCC samples examined, 22%, 16%, 32%, and 34% were positive for PD-L1, B7-H3, B7-H4, and VISTA, respectively. Nineteen samples (38%) were negative for all 4 of these markers, whereas 31 (62%) expressed at least 1 marker. None of these markers was associated with the investigated clinicopathologic variables or patient survival. PD-L1, B7-H3, and VISTA were observed significantly more frequently in SCCs than in CCCs of the cervix. Our study confirmed the expression of immune checkpoint proteins in cervical CCCs and indicated their nonredundant and complementary roles. As such, our data suggest that monotherapeutic immune checkpoint blockade may not be sufficiently effective in patients with cervical CCC.

scholarly journals Prognostic Significance of Immune Checkpoints HLA-G/ILT-2/4 and PD-L1 in Colorectal Cancer

2021 ◽  
Vol 12 ◽  
Author(s):  
Qiong-Yuan Chen ◽  
Yu-Xin Chen ◽  
Qiu-Yue Han ◽  
Jiang-Gang Zhang ◽  
Wen-Jun Zhou ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Flow Cytometry ◽  
Immune Checkpoint ◽  
Prognostic Significance ◽  
Disease Stage ◽  
Immune Checkpoints ◽  
Multicolor Flow Cytometry ◽  
Checkpoint Proteins ◽  
Ajcc Stage ◽  
Immune Checkpoint Proteins

Immune checkpoint inhibitors (ICIs) have become a promising area of research for cancer treatment. In addition to the well-known ICIs targeting PD-1/PD-L1, HLA-G/ILT-2/-4 is relatively new immune checkpoint that has been evaluated in early clinical trials in patients with advanced solid tumors. In this study, the expression of HLA-G (n=157), ILT-2/4 (n=82), and PD-L1 (n=70) in epithelial cell adhesion molecule (EpCAM)-positive colorectal cancer (CRC) cells was analyzed by multicolor flow cytometry, and the prognostic significance of these molecules was evaluated. In EpCAM+ CRC cells, the median percentages of HLA-G, ILT-2, ILT-4, and PD-L1 were 14.90%, 67.70%, 8.55% and 80.30%, respectively. In addition, a positive correlation was observed between them (all p<0.001). Higher levels of these immune checkpoint proteins are associated with lymph node metastasis. In addition to the AJCC stage (p=0.001), Kaplan-Meier survival analysis showed that higher levels of HLA-G (p=0.041), ILT-2 (p=0.060), ILT-4 (p<0.001), PD-L1 (p=0.012), HLA-GILT4 (p<0.001) and ILT-2ILT-4 (p<0.001) were significantly associated with shorter survival of CRC patients. When CRC patients were stratified by early and advanced AJCC stages, HLA-G levels were only related to the survival among CRC patients with early disease stage (p=0.024), while ILT-4 levels were significant for both CRC patients with early (p=0.001) and advanced (p=0.020) disease stages. Multivariate cox regression analysis revealed that advanced AJCC stage (HR=2.435; p=0.005) and higher ILT-4 levels (HR=2.198; p=0.063) were independent risk factors for poor outcomes in patients with CRC. In summary, among the immune checkpoints, HLA-G/ILT-2/4 and PD-L1, ILT-4 is the most significant prognostic indicator of CRC. This finding indicated that a combination of immunotherapy strategies, such as ILT-4 blockade, could improve the clinical outcomes in patients with cancer. Moreover, multicolor flow cytometry can be employed as a reliable and efficient, alternative to immunohistochemistry, for evaluating the immune checkpoint proteins expressed in tumor lesions.

scholarly journals Mifepristone Inhibited the Expression of B7-H2, B7-H3, B7-H4 and PD-L2 in Adenomyosis

2021 ◽  
Author(s):  
Xiaoyan Qin ◽  
Wenjing Sun ◽  
Chong Wang ◽  
Mingjiang Li ◽  
Xingbo Zhao ◽  
...  
Keyword(s):  
Immune Checkpoint ◽  
Immune Checkpoints ◽  
Immune Mechanism ◽  
Secretory Phase ◽  
Checkpoint Proteins ◽  
Proliferative Phase ◽  
Elevated Expression ◽  
Immune Checkpoint Proteins

Abstract BackgroundThe immune mechanism was shown to be involved in the development of adenomyosis. The current study aims to evaluate the expression of immune checkpoint B7-H2, B7-H3, B7-H4 and PD-L2 in adenomyosis and to explore the effect of mifepristone on the expression of these immune checkpoints. MethodsThe expression of B7-H2, B7-H3, B7-H4 and PD-L2 in normal endometria and adenomyosis treated with or without mifepristone was determined by immunohistochemistry analysis.ResultsIn adenomyosis, the expression of B7-H2, B7-H3 and B7-H4 was increased in the eutopic and ectopic endometria compared with normal endometria, both in the proliferative and secretory phase. Moreover, the expression of B7-H2 and B7-H3 was higher in adenomyotic lesions than in the corresponding eutopic endometria, both in the proliferative and secretory phase. The expression of PD-L2 was higher in adenomyotic lesions than in normal endometria, both in the proliferative and secretory phase. In secretory phase but not the proliferative phase, the expression of B7-H4 and PD-L2 in adenomyotic lesion showed a significantly higher level than that in the corresponding eutopic endometria. In normal endometria and eutopic endometria, the expression of B7-H4 showed elevated expression in proliferative phase compared with that in the secretory phase, while this change altered in ectopic endometria with decreased B7-H4 expression in proliferative phase than the secretory phase. In addition, the expression of B7-H2, B7-H3, B7-H4 and PD-L2 was significantly decreased in adenomyosis after treated with mifepristone.ConclusionsExpression of immune checkpoint proteins B7-H2, B7-H3, B7-H4 and PD-L2 is up-regulated in adenomyosis and down-regulated with mifepristone treatment. The data suggests that the B7 immunomodulatory molecules are involved in the pathophysiology of adenomyosis.

scholarly journals Mifepristone inhibited the expression of B7-H2, B7-H3, B7-H4 and PD-L2 in adenomyosis

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Xiaoyan Qin ◽  
Wenjing Sun ◽  
Chong Wang ◽  
Mingjiang Li ◽  
Xingbo Zhao ◽  
...  
Keyword(s):  
Immune Checkpoint ◽  
Immune Checkpoints ◽  
Immune Mechanism ◽  
Secretory Phase ◽  
Checkpoint Proteins ◽  
Proliferative Phase ◽  
Immunohistochemistry Analysis ◽  
Immune Checkpoint Proteins

Abstract Background The immune mechanism was shown to be involved in the development of adenomyosis. The aim of the current study was to evaluate the expression of the immune checkpoints B7-H2, B7-H3, B7-H4 and PD-L2 in adenomyosis and to explore the effect of mifepristone on the expression of these immune checkpoints. Methods The expression of B7-H2, B7-H3, B7-H4 and PD-L2 in normal endometria and adenomyosis patient samples treated with or without mifepristone was determined by immunohistochemistry analysis. Results In adenomyosis patient samples, the expression of B7-H2, B7-H3 and B7-H4 was increased in the eutopic and ectopic endometria compared with normal endometria, both in the proliferative and secretory phases. Moreover, the expression of B7-H2 and B7-H3 was higher in adenomyotic lesions than in the corresponding eutopic endometria, both in the proliferative and secretory phases. The expression of PD-L2 was higher in adenomyotic lesions than in normal endometria in both the proliferative and secretory phases. In the secretory phase but not the proliferative phase, the expression of B7-H4 and PD-L2 in adenomyotic lesions was significantly higher than that in the corresponding eutopic endometria. In normal endometria and eutopic endometria, the expression of B7-H4 was elevated in the proliferative phase compared with that in the secretory phase, while in the ectopic endometria, B7-H4 expression was decreased in the proliferative phase compared with the secretory phase. In addition, the expression of B7-H2, B7-H3, B7-H4 and PD-L2 was significantly decreased in adenomyosis tissues after treatment with mifepristone. Conclusions The expression of the immune checkpoint proteins B7-H2, B7-H3, B7-H4 and PD-L2 is upregulated in adenomyosis tissues and is downregulated with mifepristone treatment. The data suggest that B7 immunomodulatory molecules are involved in the pathophysiology of adenomyosis.

Immune Checkpoint Inhibitors in Patients with Recurrent Hepatocellular Carcinoma after Liver Transplantation: A Case Report and Literature Review

2020 ◽  
Vol 20 (9) ◽  
pp. 720-727
Author(s):  
Jianguo Qiu ◽  
Wei Tang ◽  
Chengyou Du
Keyword(s):  
Hepatocellular Carcinoma ◽  
Liver Transplantation ◽  
Immune Checkpoint ◽  
Graft Rejection ◽  
Checkpoint Inhibitors ◽  
Liver Graft ◽  
Immune Checkpoints ◽  
Term Survival ◽  
Liver Preservation ◽  
Programmed Death

Background: Immune checkpoint modulators, such as the programmed death protein-1 (PD-1)/programmed death ligand-1 (PD-L1) inhibitor, cytotoxic T-Lymphocyte-associated antigen 4 (CTLA-4) inhibitor have been investigated with encouraging results for hepatocellular carcinoma (HCC). However, the safety of this strategy in patients with previous liver transplantation (LT) is not well studied. Objective: To explore the safety and feasibility of immune checkpoints inhibitors in recurrent and metastatic HCC patients on a background of LT. Methods: A case of recurrent, refractory, metastatic HCC after LT, where PD-1 inhibitor was initiated, was described and related literature was reviewed. Results: There was complete remission in lung metastases and the partial radiological response of metastatic retroperitoneal lymph node to the drug with no liver graft rejection after 13 cycles of PD- 1 inhibitor injection. PD-1inhibitor, at least in this patient, was verified to play an important role in controlling tumor progression and prolonging patient survival. Conclusions: This novel drug might be a useful method to allow doctors to guarantee a better chance for long-term survival in recurrent, metastatic HCC patients with the previous LT. However, it should be used with caution in allograft recipients due to the risk of acute graft rejection, further larger, prospective studies are needed to determine optimal immunomodulatory therapy to achieve optimal anti-tumor efficacy with transplant liver preservation.

scholarly journals Recent Advances and Future Prospects in Immune Checkpoint (ICI)-Based Combination Therapy for Advanced HCC

Cancers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1949
Author(s):  
Yawen Dong ◽  
Jeffrey Sum Lung Wong ◽  
Ryohichi Sugimura ◽  
Ka-On Lam ◽  
Bryan Li ◽  
...  
Keyword(s):  
Immune Checkpoint ◽  
Cytotoxic T Lymphocyte ◽  
Checkpoint Inhibitors ◽  
Immune Checkpoints ◽  
Advanced Hcc ◽  
Oncogenic Pathways ◽  
Vegf Pathway ◽  
And Function ◽  
Endothelial Growth Factor

Advanced, unresectable hepatocellular carcinoma has a dismal outcome. Multiple immune checkpoint inhibitors (ICIs) targeting the programmed-cell death 1 pathway (PD-1/L1) have been approved for the treatment of advanced HCC. However, outcomes remain undesirable and unpredictable on a patient-to-patient basis. The combination of anti-PD-1/L1 with alternative agents, chiefly cytotoxic T-lymphocyte antigen-4 (CTLA-4) ICIs or agents targeting other oncogenic pathways such as the vascular endothelial growth factor (VEGF) pathway and the c-MET pathway, has, in addition to the benefit of directly targeting alterative oncogenic pathways, in vitro evidence of synergism through altering the genomic and function signatures of T cells and expression of immune checkpoints. Several trials have been completed or are underway evaluating such combinations. Finally, studies utilizing transcriptomics and organoids are underway to establish biomarkers to predict ICI response. This review aims to discuss the biological rationale and clinical advances in ICI-based combinations in HCCs, as well as the progress and prospects of the search for the aforementioned biomarkers in ICI treatment of HCC.

207 Small molecule inhibitors of Sec61 cotranslational translocation regulate the phagocytosis checkpoint molecule CD47

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A223-A223
Author(s):  
Jennifer Whang ◽  
Andrea Fan ◽  
Christopher Kirk ◽  
Eric Lowe ◽  
Dustin McMinn ◽  
...  
Keyword(s):  
Tumor Cells ◽  
Small Molecule ◽  
Immune Checkpoint ◽  
Small Molecule Inhibitors ◽  
Protein Translocation ◽  
Signal Sequence ◽  
Checkpoint Proteins ◽  
Cotranslational Translocation ◽  
Macrophage Phagocytosis ◽  
Immune Checkpoint Proteins

BackgroundMany tumor cells escape immune cell clearance by overexpressing CD47, a multi-pass transmembrane protein, which binds signal regulatory protein α (SIRPα) on macrophages leading to decreased phagocytic activity. Blockade of CD47/SIRPα interactions enhances macrophage phagocytosis and is being targeted with antibody-based drugs, some of which are used in combination therapies in clinical trials. A novel method to target CD47 is through the inhibition of cotranslational translocation of transmembrane proteins. Immediately after exiting the ribosome, signal sequences that are unique to each protein are directed through the Sec61 channel into the ER for extracellular expression.1 Several Sec61-targeting compounds have been identified to suppress translocation in a signal sequence-specific manner.2 We previously described Sec61 inhibitors capable of selectively targeting immune checkpoint proteins and enhancing T cell function.3 Here, we demonstrate the blockade of CD47 expression on tumor cells and enhancement of macrophage phagocytosis with small molecule inhibitors of Sec61.MethodsSec61-dependent expression of target proteins was assayed using HEK293 cells overexpressing constructs comprised of signal sequences fused to a luciferase reporter. Stimulated PBMCs or tumor cells were incubated with Sec61 inhibitors, and surface expression of checkpoint molecules were examined by flow cytometry. Necrotic and apoptotic cells were assessed by Annexin V and 7AAD labeling. Human CD14+ monocytes were differentiated to M1- or M2-type macrophages. Jurkat or SKBR3 cells were incubated with Sec61 inhibitors, labeled with a pH sensitive dye and co-cultured with macrophages to assess phagocytosis.ResultsWe identified Sec61 inhibitors that block select immune checkpoint proteins. Compounds demonstrated either selective or multi-target profiles in transient transfection screens, which was supported by decreased protein expression on activated T cells. KZR-9275 targeted multiple checkpoint molecules, including PD-1, LAG-3 and CD73, along with a potent inhibition of the CD47 signal sequence reporter. CD47 surface expression was decreased on Jurkat and SKBR3 cells following 72 hours of compound treatment. KZR-9275 treatment of SKBR3 cells induced a minor increase in apoptotic cells, which was not detected in Jurkat cells. Increased macrophage phagocytosis, especially with M2-type macrophages, was observed when Jurkat or SKBR3 cells were pre-treated with KZR-9275.ConclusionsOur findings demonstrate that Sec61 inhibitors can block the expression of CD47, a phagocytosis checkpoint protein, on tumor cells and subsequently modulate macrophage phagocytic activity. Small molecule inhibitors of Sec61 provide an opportunity to target multiple checkpoint proteins on various cell populations. Future in vivo tumor models will assess the efficacy of Sec61 inhibitors to provide combination-like therapy.ReferencesPark E, Rapoport TA. Mechanisms of Sec61/SecY-mediated protein translocation across membranes. Annu Rev Biophys 2012; 41:1–20.Van Puyenbroeck V, Vermeire K. Inhibitors of protein translocation across membranes of the secretory pathway: novel antimicrobial and anticancer agents. Cell Mol Life Sci 2018; 75:1541–1558.Whang J, Anderl J, Fan A, Kirk C, Lowe E, McMinn D, et al. Targeting multiple immune checkpoint proteins with novel small molecule inhibitors of Sec61-dependent cotranslational translocation. 34th Annual Meeting & Pre-Conference Programs of the Society for Immunotherapy of Cancer (SITC 2019): part 2. J Immunother Cancer 2019; 7: 283. Abstract 815.

Sign in / Sign up

Export Citation Format

Share Document